Final answer:
The dramatic effect of concluding the act by letting us see the murder plot as it crystallizes is to create suspense and build anticipation in the audience.
Step-by-step explanation:
The dramatic effect of concluding the act by letting us see the murder plot as it crystallizes is to create suspense and build anticipation in the audience. By revealing the plot at this point, the audience is left wondering what will happen next and how the characters will react to the unfolding events.
For example, in Shakespeare's play Macbeth, when Lady Macbeth and Macbeth plot to kill King Duncan, the audience is aware of their plan and anticipates the outcome. This creates a sense of tension and excitement.
In addition, by revealing the murder plot at this point, it allows for a deeper understanding of the characters' motivations and actions. It provides insight into their intentions and sets the stage for the consequences that will follow.